Phase-Encoded Hyperpolarized Nanodiamond for Magnetic Resonance Imaging

Area of Science:

• Materials Science
• Biophysics
• Nanotechnology

Background:

• Surface-functionalized nanomaterials are explored for theranostic applications, combining disease detection and biological process tracking via hyperpolarized magnetic resonance imaging (MRI).
• Ideal candidate materials require spinful nuclei with long spin-lattice relaxation (T1) and spin-dephasing times (T2), alongside electron reservoirs for hyperpolarization.

Purpose of the Study:

• To demonstrate the utility of nanodiamonds as versatile theranostic agents for hyperpolarized 13C MRI.
• To introduce a novel phase-contrast imaging modality based on nanoparticle spin orientation.

Main Methods:

• Utilizing nanodiamonds with intrinsic paramagnetic defect centers.
• Leveraging long nuclear T1 times (hours) and suitable T2 times for spatial resolution.
• Employing phase-encoded hyperpolarization aligned or anti-aligned with the magnetic field.

Main Results:

• Nanodiamonds exhibit properties suitable for hyperpolarized 13C MRI, including long relaxation times.
• A new imaging modality was enabled, exploiting phase-contrast unique to nanoparticles.
• Nanoparticles can be tagged and distinguished in MRI based solely on their spin orientation.

Conclusions:

• Nanodiamonds are a versatile material system for advanced hyperpolarized MRI theranostics.
• Phase-encoded hyperpolarization offers a novel method for nanoparticle imaging and comparison of bio-functionalized complexes.